Electric insulator.



P. H. THOMAS. ELECTRIC INSULATOR. APPLICATION FILED Auc.29. I9I3.

1,278,015. Patented July 16, 1918.

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ELECTRIC INSULATOR..

APPLICATION FILED AUG.29. IsIs.

1,273,01 5. Patented July IG, 191s.

2 SHEETS-SHEET 2.

i citizen of the United a resident of Upper Montclair, county of.

. STATES' FATFLNT @lllFlC/ld.

. ERCY E. THOMS, OF 'UPPER EIONTCLAR, NEW JERSEY.

ELECTRIC ENSULATGR.

Specication of Letters Patent.

*ra-tentes .mty ie, reis.

.Application llecl August 29, 191.8. Serial lo. 737,243.

To aZZ fui/tom t may concern.'

Be it lmown that l, Pelzer H. THOMAS, a States of America, and

A advantages and purposes of this type of insulator are set forth at greater length in the specication of my application for patent,

' other modifications of vplan view showing a 'parts of Fig. 6; Fig. 8 is a vertical sectional Serial No. 767,995, led May 16, 1913, to which reference is hereby expressly made.

ln the following l have described, in connection with the accompanying drawings, a number of different forms of devices illustrating the application of the principles of my invention. ln the drawings Figure l is a vertical sectional view of an insulator showing one way of practising my invention; Fig. 2 is a top plan view, partly broken away, of the insulator shown in Fig. 1;-Fig. 3 1s a view similar to Fig. 1 showing a modification; Fig. 4 is across sectional view of a device similar to that shown in Fig. 3 along the line'A-B; Figs. 5 and 6 are vertical sectional views respectively illustrating two design; Fig. 7 is a detail of one of the view of another form of insulator showing still another' way .of carrying out the principles of my invention; Fig. 9 is a vertical sectional view showing another form of insulator embodying the principles of'my invention'; Fig.,10 is. a top plan view of the device shown in 'Fig 9 with the rain guard removed; Fig. 11 is a sectional view, partly broken away, of the parts shown in Fig. 10 along the line G-H; and Fig. 12 is a vertical sectional view' of a modification of the type of insulator shown in Fig. 9.

Similar numerals of reference indicate similar parts throughout the several views.

ln constructing the main'fbody of my insulator l prefer to use a material having a high dielectric quality and one capable of nerand outer walls of being obtained of high quality and of great uniformity. Porcelain or glass are suitable materials for the purpose. certain of the parts together any suitable cement may be used and either Portland cement or cement made of litharge and glycerin will give good satisfaction. The metal suitable metal giving the desired mechanical strength and malleable cast iron or steel forgings are suitable for the purpose. The rain guards which are adapted to improve the electrical eiiiciency of the insulator and to control the distribution of the electrical iield may be of any suitable material such as galvanized iron.

The insulator shown in Figs. .l and 2 comprises a cylindrical piece of dielectric material 26, `having circular grooves l27--27 at each end thereof, midway` between the inthe cylinder. short length of pipe 28-28 is adapted to fit into the circular grooves 27 and to be cemented therein. Pipes 28 are internally screw threaded at their outer ends to receive a screw threaded metal block 29 carrying an eye or socket 30. 31 is a circular or disklike rain guard, screwed, bolted, or otherwise fastened to pipe 28 adjacent to the ends of the cylinder 26. The outer periphery of the'rain guard 31-is curled or turned' downwardly in the form of a bead 32. This may be conveniently done by turning the edge of the rain guard over a wire. The rain guard extends diametrically from the cylinder 26 a sufficient distance to prevent the rain from dripping down the cylinder while at the same time the rain guard acts as a distributer of the electric eld in order to improve the electrical eiiiciency of the device. The purpose of the bead'is to avoid a sharp edge on the rain guard and it is turned down to permit the rain to fall off gradually as it comes rather than retaining the same so that it will fall olf intermittently in larger quantities. 33-33 are air spaces between the blocks 29 and the ends of cylinder 26. Y

'In Fig. 3 the cylinder 26 is shown without the circular recesses at the ends. ln this figure the blocks 29 are provided with recesses 34 to receive the ends of cylinder 26, the blocks entering a short distance into the space within the cylinder as shown. Rain guards 31 are shown as fastened to the blocks 29 and instead of extending at right ln cementing parts of the insulator may be of any The angles to the cylinder 26 they are bent downward from the plane shown in Fig. 1.

Fig:4 shows an insulator, similar to that of Fig. 3, in which the tube or block 26 is made in three segments to accomodate the expansion and contraction of the blocks 29. In Fig. 5 the cylinder is shown in the formof' a double U-shaped piece in cross section, joined together at the top by a bridge 35, thus having air spaces 36 and 37 within the same. The blocks 29 are provided with suitable recesses to receive the respective ends of the cylinders which are cemented in said blocks. The rain guards 31 are fastened to the blocks 29. This form vprovides two cylinders of insulating material, thus giving greater strength while preventing a direct discharge through air and recessed at t e inner end to receive the upper end of cylinder 41. The top of cylinder 4.0 and the bottom of cylinder 41 are each provided with shoulders 42 to which are cemented metallic clamps 43 carrying rings 30. The rain guards 31 are shown as fastened to the clamps 43. 44-44 are metallic Acores cemented to the ends of cylinders 40 and 41 respectively and joined: together by a coupling 45 screw threaded to the inner ends'of cores 44-44 respectively so that the two parts of the insulator may be closely drawn together by rotating one with reference to the other. The ends of cylinders 40and 41 are closed by bridges 46 of dielectricvmaterial and provided with shoul v ders 47 arranged at right angles to the line ofstrain'caused by the pull of Athe cores 44-44 ofsaid cylinders.,vv The ends of the v cores,44-44 are also provided with shoulders 48 at right angles to the line of strainv above described andparallel to the shoulders at the ends of cylinders 404-41. The purposeof the shoulders 47-48 is that vwhen .the parts are cemented together the line of strain will be such as to be .perpendicular to'the cement surfaces. 49 is an air space within cylinders 40` and 41 surrounding cores 4:4--445 Y v Figs. 9, 10 and 11 show an insulator comprising af cylinder 83 of dielectric material rovided with circular iianges 84-84 and a ridge 85 separating the two ends of the cylinder from eachother. Each end of the v endsgof said cylinders.

'cylinder is provided with recesses 86 arranged circumferentially (Fig. 10) of the respective ends of the cylinder. The cylin-` der at each side of recesses 86 is flared inwardly and outwardly to form a strengthened wall for the recesses 86.4 87 is a metal cap piece carrying pins 88 adapted to be cemented in recesses 86. Rain guard 89 is preferably integral with .cap .87." The periphery of the rain guard 89 is provided with a rounded edge as shown. Rings 90 are carried by the cap pieces 87. This form provides 4a large number of small points of application ofstrain to the insulating material, which relieves the latter mechanically and at the same timeA is simple and economical to construct.

Fig. 12 shows an insulator comprising a plurality of cylinders of dielectric material, cylinders 91-91 being similar to each other and each closed at one end by a bridge'92 of dielectric material. The connection between the .cap piece 87 and the cylinder 91 is somewhat similar to that described connection with the4 insulator. shownin Fig. 9. Cylinders 91 andt 93 are4 joined together by pins cemented in recesses at the adjacent Opposite the recesses formed to receive the connecting pins the respective cylinders are flared outwardly as shown at 94 and also provided with ribs 95. The purpose 'of the ared out portion and of the ribs 95 is to strengthen `the-dielectric material opposite said recesses. The

caps 87 are connected tothe respective ends.

of 'the cylindersA 91 by means of pins 96 the lower ends of which are cemented in the recesses 86 in the ends of the cylinders while the upper ends are provided with heads 97 resting on washers 98 of any suitablev Inaterial such as asbestos, leather, lead, etc. the shank of the pin having a slight play in perforations 99 through thecap` piece 87, the

cap piecebeing provided with suitable recesses or shoulders 100 to-receive the heads 97 of pins 96. This construction is especially effective in relieving the insulating material from all stresses due to the eXpansion, contraction or deformation of the cap pieces 87. Ribs 101'are also shown as being 'disposed' adjacent the ared oultside portions of cylinders 91 opposite-the recessesv secure by Let-- 1. A line insulatorfcomprising a tube of j, I vitreous material having straight sides,

metal hanger' pieces ttedu'to each end and means fortransmitt'ing the entire load to be carried by the insulator directly from the hanger pieces to the walls of the tube.

2. A line insulator comprising a tube of vitreous material and means for transmitting the entire load to be carried by the insulator directly to the walls of the tube comprising metal hanger pieces taking directly into the tube at each end thereof.

3. A line insulator comprising a tube of vitreous material and means for transmitting the entire load to be carried by the insulator directly to the walls of the tube comprising metal end caps provided with ianges adapted to engage both the inner and the outer surfaces of the ends of the tube.

4. An insulating support comprising a i metal hanger attached to the support, a sec- 0nd metal hanger attached to the object to be supported and means for insulating said hangers from each other and for carrying the entire load to be supported, said means consisting of a tube of vitreous material having its ends tted to and secured in said metal hangers.

5. AnA insulating support comprising a supporting and insulating member of vitreous material in the form ofa hollow cylinder, end caps litted to and inclosing the ends of the cylinder and means for securing the end caps to the Walls of the cylinder whereby the entire load is carried by said cylinder.

6. In an electric insulator, an insulating, load-carrying member, comprising a tube of vitreous material, and metal end caps tted y and secured to the ends of said tube, said tube being the only mechanical connection between said end caps.

7. A strain supporting line insulator, comprising metallic end pieces attached respectively to the line conductor and the supporting structure, vand an elongated insulating tension member for connecting said end pieces, said insulating-member being of vitreous material, hollow, and having a thin wall of uniform thickness and stress resisting means for securing said end pieces to the lsourface of the wall of said insulating memapex, and an encircling flange at its base for gripping the tension member on both the inner and outer surfaces of the ends thereof.

10. A. line insulator comprising a hollow insulating member, metallic end caps there- 'for closing said hollow member and having projecting portions-adapted to engage both inside and outside the wall of said insulating member at the ends thereof.

l1. A line insulator comprising a tube of vitreous material and metallic end caps therefor closing the ends of said tube and extending beyond the side walls of the tube to form a rain guard,`said caps being provided With lianges adapted to engage both the inner and outer surfaces of the ends of the tube.

12. A line insulator comprising a tubular v tension member of vitreous material having an open end and open interiorly continuously from end to end, means for transmitting the entire mechanical load to be carried by the insulator directly to the Walls of said. tubular member, said means comprising caps of electrically conductive material respectively carried directly by the Walls of said tubular member at the ends thereof, and` means for preventing an electrical discharge v through the interior of said tubular member.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

PERCY H. THOMAS.

Witnesses:

K. G. LeAnn, ANNA JENSEN. 

